Making even the most straightforward movie is a seriously complex and challenging undertaking, with hundreds or even thousands of people working together to try and produce two hours of quality cinema.
But outside influences often end up causing unexpected changes to a movie for one reason or another, and on occasion that influence actually ends up being another movie entirely.
For one of many different reasons, another film - whether previously released or in production at the same time - can cause the filmmakers to pivot aspects of their production, such as writing, character design, tone, or perhaps even something as simple as its title.
These sorts of decisions generally cause major headaches for filmmakers who are simply trying to produce an entertaining film without having to consider what other movies are up to.
In some cases they literally had no choice but to make changes to their own film, while in others the filmmakers decided to be proactive in an attempt to get ahead of a potential problem.
In some cases it worked out perfectly, while in others the damage was sadly already done...
10. Harry Potter Forced Thor: Love & Thunder To Change Gorr's Design
If you're a fan of the Thor comics and thought that the depiction of Gorr the God Butcher (Christian Bale) in the recent Thor: Love and Thunder deviated too far from the source material, there is actually a reason for that.
During pre-production on the superhero sequel, filmmaker Taika Waititi realised that Gorr's original design in the comics - namely a flat nose, angular teeth, pale skin, and beady, sunken-in eyes - was incredibly similar to Lord Voldemort's (Ralph Fiennes) appearance in the Harry Potter movies.
And so, Waititi made the decision to change many of these elements - namely giving Gorr his nose back and making his skin less pale - to avoid inevitable comparisons between the two villains. In an interview with IGN, Waititi said:
"His face in the comics, unfortunately, does kind of resemble Voldemort. So I was like, 'People are just automatically going to make that connection.' So we decided to depart from that design and sort of keep elements of the tone, and the fact that he had the sword. Really, it was his story that was the most important thing for us."